Cleaner for heat exchange and like tubes



March 23, 1954 V. H. BAKER CLEANER FOR HEAT EXCHANGE AND LIKE TUBESFiled Dec. 22, 1947 Patented Mar. 23, 1954 CLEANER FOR HEAT EXCHANGE ANDLIKE TUBES Virgil H. Baker, Springfield, Ohio, assignor to ElliottCompany, Pittsburgh, Pa., a corporation of Pennsylvania ApplicationDecember 22, 1947, Serial No. 793,169 9 Claims. (01. 15104.14)

This invention pertains to tube cleaners, and more particularly to aswing frame cutter head for tube cleaning equipment.

The general type of cutter head shown herein, and commonly known as aswing frame or swim;- ing arm cutter head, is in everyday use byindustry. There are, however, certain inherent disadvantages in thestructural arrangement of the component parts comprising the presentlyused cutter heads. Such disadvantages have been heretofore known, andmany efforts made to eliminate such deficiencies. cutter head which issubjected to centrifugal force, extreme pressures are created within theparts of the head, making such cutters subject to excessive wear andbreakage. Many different constructions have been proposed and used in aneffort to reduce this excessive wear and breakage to a minimum, none ofwhich, however, have been wholely successful. The present invention-isdirected to a structure which under actual working conditions hascompletely eliminated the heretofore-objectionable breakage andexcessive wear.

The object of the invention therefore is to improve the construction aswell as the means and mode of operation of centrifugally actuated cutterheads, whereby they may not only be economically manufactured, but willbe more efficient in operation, uniform in action, of longer life, andbe unlikely to get out of repair.

A further object of the invention is to improve the construction of suchcutter heads whereby excessive strains are eliminated.

A further object of the invention is to provide a construction in whichtorsional and shearing strains'upon the parts of the head are reduced toa minimum.

A further object of the invention is to provide a construction in whichthe critical elements are subjected to compressive forces while the headis under the influence of centrifugal force.

A further object of the invention is to provide a locking member usablein such cutter heads which effectively prevents longitudinal androtational movement of its associated member.

A further object of the invention is to provide locking means in suchcutter heads having relatively few parts which may be quickly and easilyassembled.

A further object of the invention is to provide a centrifugally operatedcutter'head having the advantageous features, the inherent meritoriouscharacteristics and the mode of operation, or their equivalents, ashereinafter described or shown in the accompanying drawing.

Due to the type of With the above primary and other incidental objectsin view as will more fully appear in the specification, the inventionintended to be protected by Letters Patent consists of the features ofconstruction, the parts and combinations thereof, and the mode ofoperation, as hereinafter described or illustrated in the accompanyingdrawings, or their equivalents.

In the drawing, wherein is shown the preferred but obviously not theonly embodiment of the invention,

Fig. l is a perspective view of a centrifugally operated cutter headembodying the present invention.

Fig. 2 is a fragmentary side elevation, partly in section, of a cutterhead embodying the present invention.

Fig. 3 is a fragmentary sectional view taken on line 33 of Fig. 2.

Fig. 4 is a perspective view of the locking member.

Like parts are indicated by similar characters of reference throughoutthe several views.

Referring to the drawings, there is shown in Fig. 1 a perspective viewof a centrifugally actuated cutter embodying the present invention andcomprising a central frame member or spider I upon which the remainingparts of the head are pivotally supported. Each end of the spider has aseries of longitudinally aligned radially projecting lobes 2--3 thereonwhich serve as the mounting means for the swinging arms. Supportedbetween the lobes 23' upon arm pins 4 are swinging arms 5, comprising asubstantially U- shaped member having a central portion 6 andtransversely extending terminal members 'l8. The swinging arm 5 ispivotally secured between each pair of lobes 2- 3 upon the arm pin 4which passes through aligned bores within the lobes 23 and the centralportion 6 of the arm.

The transversely extending terminal members 7-8 of the swinging arm 5have aligned bores in their outer extremities through which pass outterpins 9 having enlarged heads l0 thereon. A series of freely rotatingcutters II and I2 are mounted upon the cutter pins 9, the tapered cutterll being mounted on the pin in engagement with the head Ill before thepin is passed through the front member 8. The series of straight cuttersl2 are then assembled on the pin and the pin then passed through therear terminal member 1.

The arm 5 with the cutters assembled thereon is then placed in thespider and the arm pins .4 inserted to mount the arms on the spider. Ahead coupling I 3 is then assembled on the spider l, a flange l4 uponthe coupling engaging the heads l5 upon the arm pins s to retain thepins in assembled position.

The head coupling [3 is attached to an appropriate source of power torotate the cutter head. Upon rotation thereof the arms ii swingoutwardly under centrifugal influence thereby engaging "the, cutters I!and I2 with the interior walls of a tube being cleaned. The cutters arerotated upon the cutter pins by the frictional engagement thereof withthe tube wall. The speed of rotation of the spider 'I being rela: tivelyhigh, the rotational speed of the cutters upon the cutter pins becomes.fiOt s fifi -fabiy greater, creating great stress upon the cutter andthe terminal member of the swinging arms.

The cutter pins 9 have the greatest strain, and are subject to thegreatest wear due to the high speed rotation of the cutters thereon. Ifunanchored, the pins 9 oi course would tend to revolve with the cutters,causing excessive wear notonly to the pins 9 but to the swinging arms 5?For. this. reason, the. pins 9 must be restrained, andinore or lesslocked position within the swinging arms 5.

'Vai ious methods and structures have been proposed toaccom'plish thislocking or holding of the cutter pins, all or which have striven to'produce a fixed locki'ngfmeans that would prevent all movement of thepins relative to the swinging arms 5. This, however, has never provensatisfactory, since if positively held; in position, the pins in a veryshort time crack or break due to metal fatigue caused by the vibrationof the. pin relative to a fixed point. Such locks have 'talgn the formof nuts threaded on the' cutter pins, or thetlireading of the cutterinto the rear member l of the swinging arm 51 Other. means of lockingthe pins. have, been proposed such as substantially C-shaped' loci;- ingplates for engagement with recessed ornattened terminals on thefp'ins.This iorrnoiloci;- ing means hasfproven very unsatisfactory since theiu'rcations of the locking plate between which the. pin. is" locatedvery soon. weaken and brealt under. the. continuous torsional andshearing strain, placed. thereon by the attempted rotation o the, cutterpin.

The various disadvantages of these. prior. as-

semblies havefbeen overcome by arelatively simple, but quite' efiectivelocking member which is soinstalled within the assembly comprising thecutterhe'ad that thef member is subjected only to fcompressive forces,resistanfie tov which forces represents'the greatest strength of thelocking men bei' f T he described locking member; tuneas a latch inconnection with the'cutter, pin,

and, since it is interposed between, the cutter and arm, pins, may bedescribed as a thirdpin.

The outer. facesof the rearv terminal members I of theswinging arms 5.are. recessed as shown at 1.5, such recess interconnecting the,transverse bores through which the cutter pins 9 and, arm pinsA-exten d.The width ofithe recess I5 is sub.- stantially. equal to the diameter ofthe, trans-j verseiborfe through which the arm pin- 6; extends.

The cutter. pin 9 ha a transverse notch i w re he i e b u t ntial; re?ment with. themecess [5. when the pin Q isfully inserted. through. theterminal members I, and 8; ofthesvvingingarm 5,

te s? 1 bar t sh w F a av n a! qia e l l rmina ermi a d: i eei l ieasava a twater e minar r ee minal end Is at its opposite end is soproportioned as to fit within the recess 15 of the terminal member 7 onthe arm 5. The length of the locking bar I! is such that when theterminal I8 thereof is seated within the notch IS in the cutter pin 9,the opposite terminal 49 thereof is located in concentric relation withthe transverse bore through which the arm pin 4 projects. The radius ofcurvature of the semicircular terminal [9 is substantially equal to theradius. of the bore within the member I.

In assembling the unit, the cutters 15-42 are assembled upon the cutterpin 9 as before explainedand the Pin. inserted in its supporting boreswithin the. terminal members 5-3 of the arm 5. The locking member I! isthen placed in the recess [5, the rectangular terminal is thereof beingadjacent the cutter pin 9. The bar I! is then moved so that the terminal(3 thereof enters the notch it in the pin 9, thereby aligning theopposite semi-circular terminal 59 with the bore through which the armpin 4 projects. The arm is then placed, intermediate the lobes 2 3 onthe spider I in alignment with the transverse bores therein and the armpin t inserted; tl'ierethrou gh. The pins r2 are retained in posi o b thuplin he l l and s ated flange I},

Upon ss m 9 h rm 5 a r-r i l;- ter pin a a kin ba w n th anes:

-1 h s d L h ot ins me la r it t i d l i h 9 5.: y. he; v r a r ae n aemen c the o es her ith- MQ Qr m nt tt l c in l? q situdiaa lr f 1 7 5 wh -2Q) 25 9 313? v nted- Simultaneously with the assembly oi the arm toe ide t. he eq aneu ar mina 0f th locking mfi ber. ente s the. wi it thecutter pin 9- and is retained therein by the m n 1 mm Wh sk he mi-t ndererm-i;- nal Id of the locking member rests.

o itu nal movemen e. ut e P1 3; thereby prevented bythe retention ofthelook; s ember 1- t n h e 5 ndhe r rin en agem the ot h ela i t er inais o e o n mem otational movementof the cutter-pin 9 is also pren e byement he o kin member H within the. notch I 6,

Such rotational movement causes the greatest tr in. upon g qk e. mem rtim he orc d em i a o ati he-put er i -l2;

on the pin 9 are considerably greater than; the.

e de r eme. t m r qns tudinallv of the cutter head. Suchexcessive forceis transe m me. q ha p in emb r ll n q a t: ion that the locking memberis placed coint s at er h n. r t n a he r n o or- 1 m s a n er n.- Eh at on. i h orce ppl dr q he n m mbe J; up n p atiqnra1 nt, of; h in. s.ully aken. b he rm re n m. wh tht e s m -c cul r. e mina 1910f urk ng.membe s suppe -ted and; th

e: f th ece s. 5-. r ch onstuefiomthe:

r a ren th Q h me membe l namely compression, is utilized.

A t u e q ne emb r; 11 fiec ivelr.

en s bo h. n udin nd o ation zmeve ment of the cutter pin 9, suchlocking orholding oi; thepin is, not; in the sense of; aniab$01ute and xd l ki here as w ld; e v pon. h eaded, enga e e t. the pin- With theern-lie alz m ber 1 r bsr c t ne hepin.bymeansoi:

b t;- nea ti ewi h Suff c e lo seness. or

play is permitted so thatthe-cutter pin fl willnot,

5. break from fatigue caused by continued vibration and strain opposedby an absolutely fixed mounting of the pin within the terminal member 1.

The present construction has been found quite satisfactory in actualuse, it being far superior to the more conventional assemblies embodyingmeans for fixedly securing the cutter pin 9 to the swinging arm 5. Acutter head having a longer life, with fewer replacements and repairshas resulted from the use of the present structural features in suchequipment.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantage before enumerated as desirable, but whichobviously is susceptible of modification in its form, proportions,detail construction and arrangement of parts without departing from theprinciple involved or sacrificing any of its advantages.

While in order to comply with the statute the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown; but that the means and construction herein disclosedcomprise the preferred form of several modes of putting the inventioninto effect, and the invention is therefore claimed in any of its formsor modifications within the legitimate and valid scope of the ap pendedclaims.

Having thus described my invention, I claim:

1. In a tube cleaner of the swinging arm type having an arm pin uponwhich the arm is pivotally mounted and a series of freely rotatablecutters carried by a cutter pin normally loosely mounted within theswinging arm, means for locking the cutter pin against longitudinal androtational movement relative to its supporting arm, including a bar, arectangular terminal on one end thereof, a concave semi-circularterminal on the opposite end thereof, a recess in the swinging armwithin which the bar is seated intermediate the cutter pin and arm pinwith the concave semi-circular terminal thereof in engagement with thearm pin, means for engaging the rectangular terminal of the bar with thecutter pin including a transverse notch in the cutter pin in alignmentwith the recess within which notch the bar is engageable upon engagementof the arm pin therewith, the surfaces of the notch and the terminal endof the bar so shaped that the bar is subjected to compressive forcesonly upon attempted rotational movement of the cutter pin relativethereto, and means for holding said bar in said recess upon assembly ofthe swinging arm upon the arm pin.

2. A tube cleaner of the type wherein a series of revoluble cutters areloosely mounted upon a cutter pin supported upon a centrifugallyactuated swinging arm pivotally secured to a mounting head by aremovable arm pin in parallel spaced apart relation to the cutter pin,characterized by a bar transversely disposed between the cutter pin andarm pin, interengaging configurations on the terminals of the bar andadjacent pins, one terminal end of the bar resting upon the periphery ofone pin, a transverse notch in the other pin within which the oppositeterminal end of the bar rests, and a recess in the swinging arm withinthe confines of which the bar is located to prevent both lateral andangular displacement of the bar, the surfaces of the transverse notchand the terminal end which is engaged thereby being such thatrotational-move ment of one of the pins is prevented and the forcescreated thereby absorbed by compressive reaction of the barthereagainst. 1 r

3.- In a tube cleaner of the character described having relativelyspaced parallel cutter and arm pins and supporting means therefor, amember interposed between said pins with one terminal end in abuttingengagement with the arm pin, a transverse notch in said cutter pinreceiving the opposite terminal end of said member, the surfaces of saidopposite terminal end and the notch being so shaped to preclude relativerotational movement of the pin, the force exerted by the cutter pinthereon being transferred to the member in the form of direct thrustpressure, the reaction to which is provided by the arm pin throughdirect thrust engagement of the member therewith.

4. In a tube cleaner of the character described having relatively spacedparallel cutter and arm pins and supporting means therefor, a lockingmember therefor whereby rotational movement of thecutter pin isprevented, characterized by an elongated bar transversely disposedintermediate the cutter and arm pins, a transverse notch in one of thepins within which one terminal end of the bar is seated for a resolvingof rotational impulses of said pin into an axial thrust of said bar, thesurfaces of said one terminal end of the bar and the notch being soshaped to preclude relative rotational movement of the pin, asemicircular terminal on the opposite end of the bar the radius of whichis substantially equal to the radius of the other pin upon the peripheryof which the semi-circular terminal of the bar rests in abuttingengagement therewith.

5. In a centrifugally operated tube cleaner having relatively spacedcutter and arm pins transfixing a swinging arm assembly, supportingmeans for said pins, means for locking the cutter pin against bothlongitudinal and rotative movement, including a transverse notch in theperiphery of the cutter pin, a locking bar having one terminal endseated within such notch, a thrust seat upon the opposite terminal endof the bar having abutting engagement with the periphery of the arm pin,the surfaces of the notch and the terminal end seated therein being soshaped that the thrust created by rotative movement of the cutter pin isequalized by the reactive force of the arm pin exerted through thelocking bar, and a recess within th swinging arm within which the bar isconfined to prevent movement thereof longitudinally of the arm pin inone direction.

6. A device of the class described having a pair of parallel relativespaced pivot pins mounted in a common support and normally revoluble onerelative to the other, characterized by a third pin transverselydisposed relative to the pair of pivot pins, one terminal end of saidthird pin being received in interlocking engagement within a transversenotch having a surface conforming to the surface of said one terminalend and formed in the opposite terminal end of said third pin havingabutting engagement upon the other of said pivot pins, the surfaces ofthe notch and the terminal end seated therein so shaped as to precluderelative rotational movement of the pin, and an enclosure within thecommon support within which the third pin is retained in relativelyfixed relation therewith.

7. In a tube cleaner of the character described having relatively spacedparallel cutter and arm pins and supporting means therefor, a latchacre-pee member extending; end-wise between said pins, Said memberhaving its one terminal end. sea-ted on the periphery of said arm pin inabutting en gagement therewithand. extending radially to.- ward, saidcutter pin, and interengaging portions on said cutter pin and theopposite terminal end of said. latch member, the surface portion of thecutter pin and the opposite terminal end so shaped as to resolve arotary impulse of said cutter pin into an axial thrust upon said latchmember, the said interengaging portion on said cutter pin including atransverse notch inthe periphery thereof receiving the said, oppositeterminal end. of said latch. member and having a surface conformingthereto;

8. A device of the class described having a pair of; parallel,relativelyspaced pivot pins mounted in a common: support, a latch memberextendin endwise between said pivot pins, a connection between one ofthe terminal ends of said latch 20 member and one of said, pinsresolving a rotatable impulse in said one pin into an axial thrust of;said, latch member, said connection including a transverse notch in theperiphery of said one pinv receiving the said one terminal end of saidlatch member, the surface of the notch and the terminal end engagedtherein. so shaped. as to prevent rotational movement of the one pin anda bearing surface in the opposite terminal end of said latch member inabutting engagement with said, other pin for the absorption by saidotherpin or said axial thrust.

9. A device according to claim 8, characterized by a. recess mountingfor said latch member in said support, precluding lateral shiftingmotion of said member.

VIRGIL H. BAKER.

References Cited in the file of this patent UNI'IED era-res: PA'IENTSNumber Name Date 942,778 Elliott Dec. '7, 1909' 958,118 Hauer May 17',1910' 1,658,617 Swartz et a1 Feb. 7-, 1928 1,921,019 Young Aug. 8, 19331,932,999 Young Oct, 31, 933'

